Ectoparasitic Pediculosis in Rats

Blood sucking lice are common ectoparasites (parasites that infest the outside of the body) of wild rodents. Also called pediculus, these types of parasites are relatively uncommon in pet rats and are sometimes acquired when a domestic rat comes into contact with a wild rodent.

You can suspect a lice infestation if your rat is scratching much more than usual. Apart from causing uneasiness and irritation to the rat, lice infestation can also lead to enough loss of blood that a condition of anemia can develop. Left untreated, anemia can lead to death.

Lice infestation of rats is not zoonotic in nature, since the type of louse that infects rats is specific to rodents. Human handlers of infested rats are at no risk of becoming infested with lice.

Symptoms and Types

• Visible lice and eggs on the skin/hair
• Intense scratching
• Restlessness
• Weakness (due to anemia)

Causes

Pet rats are known to acquire lice mainly through contact with wild rodents. This typically occurs when a wild rodent is able to come into close enough contact with your pet rat that the lice are able to cross over to your pet rat’s body or to its living environment (such as bedding, litter).

Diagnosis

Lice infestation can be diagnosed by identification of the adult lice or the presence of eggs on the rat’s skin and hair. Clinical symptoms that are observed may give a general indication of the severity of the problem at hand. If your veterinarian suspects anemia, a complete blood count will show if your rat is suffering from a decreased red blood cell count.